1. Field of the Invention
The present invention relates to winches, more particularly, the present invention relates to manual marine winches designed to minimize binding, simplify unloading and limit the amount of available rope that can be stored on the winch drum.
2. Background Information
Winches have been used in many applications. Manual winches have been widely used in barges, tow boats and the like. Typically a manual winch is attached to a boat deck and spools a towing cable on a rotating drum.
Manual winches remain in common use where a powered winch would be impractical or inefficient. Even in a manual winch the operator, through various mechanical advantages, can generate a very large tension on the cable. Examples of manual winches are described in greater detail in U.S. Pat. No. 5,947,450 which is incorporated herein by reference. Examples of manual winches are sold by W. W. Patterson Company and Nashville Bridge Company.
In a conventional marine winch a wire rope, the winch line, is spooled back and forth around the rotating drum and the winch line is subject to very large loads. The high loading can cause the outer layers of wire rope to become fouled, jammed or begin binding within the spaces between the lower level wire ropes. Further, rapid tension release in existing wire rope winch systems can result in what is known as “bird-nesting” of the spooled wire rope. This can make unwinding the winch very difficult in subsequent operation, and often requires a second deck hand to assist in the unwinding of the wire rope, or even the engine power of the tow boat.
Companies that utilize certain selected lashing arrangements repeatedly will often have a winch wire take up requirement (i.e. total adjustment length of the winch line) that is much less than the wire rope length attached to the winch. Further, controlling the total winch line adjustment in such situations can be used to assure that the deck hands are making the same lashing arrangements in the same proper manner. In other words a winch with a controlled total winch line adjustment or take up can assure the proper lashing configuration or rigging is followed.
It is an object of the present invention to minimize the drawbacks of the existing manual winches and to provide a simple easy loading and unloading marine winch that minimizes fouling, binding, jamming, bird-nesting, and essentially forces that a proper lashing configuration be followed.